As a microprocess technique, is known a photolithographic technique in which a negative photosensitive resin is subjected to exposure and development to form a pattern and a structure. This technology is used in a wide variety of applications, for example, production of semiconductor integrated circuits, production of masks for semiconductor exposure and production of various MEMSs. As an example of the application to the production of MEMSs, such application is advanced in various small-scale sensors, micro-probes, thin film magnetic heads, ink jet recording heads, etc. A stepper using the i-line as a light source is widely used as a device for conducting exposure. In the field of this technology, it has been required in recent years to produce a structure having a more complicated and minuter structure, and there has thus been a demand for development of a negative photosensitive resin capable of forming a fine structure exhibiting high accuracy to light from a light source through a photomask.
PTL 1 discloses, as an example of the negative photosensitive resin, a photosensitive resin composition containing a polyfunctional epoxy resin and a cationic polymerization initiator.
PTL 2 discloses, as an exemplary ink jet head in the application to the production of MEMSs, a device containing nozzles for ink jet head, said device ejecting an ink droplet by causing a bubble formed by heating a heating resistor to communicate with the air.